Easily removed heatsink clip

ABSTRACT

A clip is disclosed which is capable of applying significant retention force via a rotatable cam arm while being easily removable due to the cam arm and a separate removal arm. A method of using the clip is also disclosed which uses the advantages of the clip, particularly in the context of computer design and construction.

FIELD OF THE INVENTION

[0001] The present invention generally relates to the field ofmechanical fasteners, and particularly to retention clips, specificallyheatsink retention clips used to anchor heatsinks to heatsink retainers.

BACKGROUND OF THE INVENTION

[0002] This section is intended to introduce the reader to variousaspects of art that may be related to various aspects of the presentinvention, which are described and/or claimed below. This discussion isbelieved to be helpful in providing the reader with backgroundinformation to facilitate a better understanding of the various aspectsof the present invention. Accordingly, it should be understood thatthese statements are to be read in this light, and not as admissions ofprior art.

[0003] In the field of computer design, processing chips, which performthe computational functions of a computer, typically generatesubstantial amounts of heat. This heat must be dispersed from around thechip to prevent malfunctions. To accomplish this, heatsinks aretypically associated with the chips to provide a structure with highsurface area to disperse the heat. As processing chips have grown bothfaster and hotter, heatsinks have grown proportionately larger andheavier. For example, current heatsinks may weigh more than a half poundto achieve the desired heat dissipating effect.

[0004] Retention clips are typically used to secure the heatsink to aheatsink retainer which positions the heatsink relative to the heatgenerating chip. As heatsinks have grown larger and heavier, theretention clips must in turn be stronger to avoid shifting. If aretention clip is too weak to secure the heatsink during shipping, theheatsink may pull loose, allowing the processing chip to come unseateddue to their interface.

[0005] In addition to strong retention clips, however, there is also aneed to make the clips easy to install and remove. Current clips musteither be removed with a screwdriver or other tool or with a release tabor other mechanism requiring the application of significant force evenafter the release of any locking mechanism. Additionally, the use ofrelease tabs and levers typically result in retention clips whichenlarge or exceed the heatsink envelope, thereby increasing thefootprint of the assembly and limiting the height of nearby elements.Such clips are difficult for factory personnel to remove not only due tothe need to use a tool within a confined space to effect removal butalso due to the force necessary remove the stronger clips. Ideally, aretention clip would require low installation force, would possess highretention force, and would be easily removable.

SUMMARY OF THE INVENTION

[0006] The following passage is intended only to provide a brief summaryof limited aspects of the present inventions and should not be construedas encompassing all necessary elements or steps of the inventions. Thepresent invention is related generally to overcoming the deficienciesinherent in previous designs by allowing easy insertion and removal of aretention clip while providing adequate retention force. This aim isaccomplished by providing designs comprising a simple release generallyin the form of a pinchable release mechanism. Additionally methodologiesare provided which include the act of using a pinchable releasemechanism to effect the release of a heatsink retention clip.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] The invention will hereafter be described with reference to theaccompanying drawings, wherein like reference numerals denote likeelements, and:

[0008]FIG. 1 is a cutaway view of a idealized computer system includingan exploded view of a heatsink assembly;

[0009]FIG. 2 is a side view of a heatsink retention clip;

[0010]FIG. 3 is a perspective view of a heatsink retention clip in thelocked position; and

[0011]FIG. 4 is a perspective view of a heatsink retention clip in theunlocked position.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0012] It will be appreciated that the present invention can take manyforms and embodiments. Some embodiments of the invention are describedso as to give an understanding of the invention. It is not intended,however, that the embodiments of the present invention that aredescribed in this specification should limit the invention.

[0013] Turning now to the drawings and referring initially to FIG. 1,there is depicted a cutaway, perspective view of an exemplary computersystem 10. Computer system 10 comprises a chassis 14 which in turn iscomprised of a number of chassis walls 18.

[0014] In addition, computer system 10 comprises a motherboard 22.Motherboard 22, in turn, comprises a board substrate 26 and componentssuch as central processing unit 30, and memory components 34. Disposedabout CPU 30 on motherboard 22 is a heatsink retainer 50. Mass storagedevice 38 also resides within the chassis and is connected tomotherboard 22. In addition, computer system 10 comprises input andoutput devices such as monitor 42 and keyboard 46.

[0015] In the illustrated embodiment, heatsink retainer 50 possessesclip engagements 62 along the edges and generally disposed about thecorners. As depicted, each clip engagement 62 is configured to receive ahooked member 94 comprising a part of a retainer clip 58. Alternativelyclip engagement 62 may be configured as a projection such that theprojection fits into a cutout window comprising a part of retainer clip58.

[0016] In computer system 10, heatsink 54 is conformably engaged withretainer 50 such that the bottom of heatsink 54 is in contact with CPU30. In the preferred embodiment, two retainer clips 58 are disposedalong heatsink upper faces 78 and securely engage with clip engagements62 of retainer 50 via hooked members 94. As depicted in FIG. 1, retainerclip 58 further comprises a cam arm 102 and a removal arm 98 whichprovide for easy engagement and removal of retainer clip 58 in thelimited space of chassis 14.

[0017] As depicted, the heatsink assembly, comprising heatsink retainer50 and heatsink 54, defines a three-dimensional spatial envelope. Asillustrated, the addition of retainer clip 58 does not substantiallyincrease the size or change the shape of the envelope. In an exemplaryembodiment, the footprint of the envelope is generally square andremains square even after the addition of retainer clip 58.

[0018]FIG. 2 depicts an embodiment of the retainer clip of the presentapplication. Retainer clip 58 is shown to comprise a clip body 82 ofgenerally elongated nature. Clip body 82 comprises a clip top surface114 and a clip bottom surface 118. Each end of clip body 82 comprises aretaining arm, a first retaining arm 86 and a second retaining arm 90,projecting downward relative to bottom surface 118. On the distalportion of first retaining arm 86 and second retaining arm 90 are hookedmembers 94 which serve to engage clip engagement 62. Alternatively,first retaining arm 86 and second retaining arm 90 may comprise cut outwindows on their distal portion which engage conforming projectionsinstead of clip engagements 62.

[0019] Additionally, clip body 82 comprises a removal arm 98 on one endprojecting upward relative to top surface 114. Removal arm 98 may be alooped structure when clip body 82, first retaining arm 86, secondretaining arm 90, and removal arm 98 all comprise a single unitarypiece.

[0020] Retainer clip 58 also comprises a cam arm 102 generally centeredalong clip body 82. Cam arm 102 has an arm body 130 connected to two armrunners 134 such that each is located on a different side of arm body130 and configured to span the width of clip body 82. Each runner 134comprises a hinge hole 138 configured to receive a corresponding hingepin 142 projecting from the side of clip body 82. The coupling on hingepin 142 and hinge hole 138 allow cam arm 102 to partially rotaterelative to clip body 82. Each runner 134 further comprises two pair ofaligned, inward facing protrusions a pair of unlock protrusions 146 anda pair of lock protrusions 150. Both unlock protrusions 146 and lockprotrusions 150 act to hinder, but not prevent, the free rotation of camarm 102 relative to clip body 82 effectively preventing rotation of camarm 102 absent the application of some minimal level of force.

[0021] Cam arm 102 may further comprise a lifting member 106 which isconfigured such that, when cam arm 102 is rotated generallyperpendicular to clip body 82, lifting member is angled slightly awayfrom clip body 82. Cam arm 102 also comprises rotation stop 122configured to prevent rotation of cam arm 102 when cam arm is generallyperpendicular to clip body 82.

[0022] In the embodiment illustrated in FIG. 2, cam arm 102 is connectedto clip body 82 by hinge hole 138 and hinge pin 142 such that therotation of cam arm 102 is toward removal arm 98. Rotation stop 122,however, prevents rotation toward removal arm 98 past a point which isgenerally parallel to removal arm 98 and generally perpendicular to clipbody 82.

[0023] Referring now to FIG. 3, Retainer clip 58 is shown from abirdseye perspective in a locked configuration which would be typical ofnormal operation in the preferred embodiment. Longitudinal axis 126 isshown for reference running in the direction of clip body 82. In thelocked configuration cam arm 102 is rotated such that it is generallyparallel to clip body 82. In this position, lock protrusions 150 act toimpede the free rotation of cam arm 102 from the locked position. Aforce exceeding some minimum required force must be applied to cam arm102 to overcome the resistance of lock protrusions 150 when locking orunlocking the cam arm. Additionally, as depicted lifting member 106 androtation stop 122 each are angled away from top surface 114 of clip body82 when cam arm 102 is in the locked position.

[0024] As is also depicted in FIG. 3, in the locked position, runners134 extend downward along the sides of clip body 82 in the samedirection as the retaining arms 86, 90. Thus, referring back to FIG. 1,in the locked position, runners 134 exert force on heatsink upperface 78and thereby securely hold heatsink 54 against CPU 30. In the lockedposition, clip bottom surface 118 is therefore not in contact withheatsink upper face 78. In this manner, the mechanical force generatedby hinged cam arm 102 in conjunction with the engagement of hookedmembers 94 with clip engagements 62 allows greater force to be appliedin securing heatsink 54 than would be possible in the absence of cam arm102.

[0025] Referring now to FIG. 4, retainer clip 58 is shown from abirdseye perspective in an unlocked configuration which would be typicalof removal or insertion in the preferred embodiment. To effect insertionof retainer clip 58, referring also to FIG. 1 for context, it will bepresumed that heatsink 54 is disposed in an unsecured manner uponheatsink retainer 50. Retainer clip 58, while in an unlockedconfiguration, is then placed upon heatsink 54 such that clip bottomsurface 118 rests on heatsink upper face 78.

[0026] To achieve this position a downward force will be applied toretainer clip 58 so that hooked members 94 can overcome the resistanceprovided by clip engagements 62. The rounded edges of hooked members 94help to facilitate sliding past clip engagements 62. Alternatively, apinching force my be applied to removal arm 98 and parallel cam arm 102to provide a bend to clip body 82 and to thereby further separate theretaining arms 86, 90. In this manner, hooked members 94 may more easilybe pushed past clip engagements 62. When hooked member 94 are inposition relative to clip engagements 62 and when clip bottom surface118 is resting upon heatsink upper face 78, cam arm 102 may be rotatedto a locked position to secure heatsink 54 to CPU 30. To effect thisrotation of cam arm 102, the resistances provided by unlock protrusions146 and lock protrusion 150 must be overcome with a sufficient force.

[0027] To effect removal of retainer clip 58 from a locked position camarm 102 is rotated from the locked position, generally parallel to clipbody 82 to the unlocked position, roughly parallel to removal arm 98.This is done by overcoming the resistances provided by lock protrusions150 and unlock protrusions 146. Once in the unlocked position, runners134 will no longer be securing heatsink 54 to retainer 50, and hookedmembers 94 should be disengaged from clip engagements 62. If hookedmembers 94 are not disengaged from clip engagements 62 a downward forcemay be applied to retainer clip 58 to achieve this disengagement.

[0028] Next a pinching force is applied using removal arm 98 and nowparallel cam arm 102. The pinching arm effects a distortion of clip body82 which acts to further separate the retaining arms 86, 90. Theseparation of the retaining arms 86, 90, and therefore the separation ofhooked members 94, allows for easy lifting of hooked members 94 pastclip engagements 62. Once hooked members 94 are clear of clipengagements 62, retaining clip 58 may be easily and completely removedfrom the heatsink assembly. As noted above, an alternative embodimentwould replace hooked member 94 with windowed cutouts and clipengagements 62 with fitted projections. However, operation of theretainer clip 58 would remain the same in this alternative embodiment.

[0029] Due to the presence of the partially rotatable cam arm 102 andremoval arm 98, removal of retainer clip 58 can be accomplished withoutthe use of any tools, such as a screwdriver or other prying instrument.The pinch removal system combined with the mechanically efficient hingedcam arm allows the use of a more powerful retainer clip, a necessity dueto the increasing weight of heatsinks, while still allowing easyinsertion and removal. In one exemplary embodiment, the retainer clip ofthis application is capable of applying the 70 lbs. of force to securelyhold a heatsink, thereby preventing a processor from pulling out in adrop test.

[0030] While the invention is susceptible to various modifications andalternative forms, specific embodiments have been shown by way ofexample in the drawings and have been described in detail herein.However, it should be understood that the invention is not intended tobe limited to the particular forms disclosed. Rather, the invention isto cover all modifications, equivalents and alternatives falling withinthe spirit and scope of the invention as defined by the appended claims.

What is claimed is:
 1. A retainer clip comprising: an elongated bodywherein the elongated body comprises a top surface and a bottom surfaceand a first end and a second end; a first retaining arm extending fromthe first end generally downward from the bottom surface; a secondretaining arm extending from the second end generally downward from thebottom surface; a removal arm extending from either the first or secondend generally upward from the top surface; and a cam arm attached to theelongated body by a hinge mechanism and extending outwardly from the topsurface wherein the cam arm may be rotated toward the removal arm tolock a retained component to a retaining member.
 2. The retainer clip ofclaim 1, wherein the elongated body, first retaining arm, secondretaining arm, and the removal arm all comprise a single piece.
 3. Theretainer clip of claim 2, wherein the removal arm comprises a loopedstructure.
 4. The retainer clip of claim 1, further comprising a firsthook member located on the distal end of the first retaining arm and asecond hook member located on the distal end of the second retainingarm.
 5. The retainer clip of claim 1, further comprising a first cutoutand a second cutout located on the first retaining arm and the secondretaining arm respectively.
 6. The retainer clip of claim 1, furthercomprising a lifting member on the distal portion of the cam arm whereinthe lifting member is angled relative to the cam arm such that thelifting member is not parallel to the elongated body when the adjacentcam arm is parallel to the elongated body.
 7. The retainer clip of claim1, wherein the cam arm comprises a rotation stop configured to contactthe top surface when the cam arm is generally perpendicular to theelongated body such that the rotation stop prevents further rotation. 8.The retainer clip of claim 1, wherein the cam arm comprises two runnerstructures such that when the cam arm is generally parallel to theelongated body the runner structures extend past the bottom surface andwhen the cam arm is generally perpendicular to the elongated body therunner structures are substantially above the top surface.
 9. Theretainer clip of claim 8, wherein the runner structures each comprise aninward protrusion, configured to be in alignment, such that rotation ofthe cam arm from a locked position is impeded but not prevented.
 10. Aretainer clip comprising: a main body; a connector member to engage themain body to a retaining member; a rotatable arm wherein the arm may berotated between a locked position and an unlocked position such that thelocked position causes a securing force to be applied to a retainedcomponent disposed between the main body and the retaining member; and adisengaging member disposed such that a pinching force may be applied tothe disengaging member and to the rotatable arm in the unlocked positionsuch that the connector member disengages the main body from theretaining member.
 11. The retainer clip of claim 10, wherein theretained component comprises a heatsink and the retaining membercomprises a heatsink retainer.
 12. The retainer clip of claim 11 whereinthe heatsink, the heatsink retainer and the retainer clip spatiallydefine a heatsink envelope such that the retainer clip does notsubstantially increase the size of the heatsink envelope.
 13. A methodof removing a retainer clip comprising: raising a rotatable cam arm froma first position relative to a retainer clip body to a second position;squeezing the cam arm and a removal arm together so that the retainerclip body is temporarily deformed such that a first latching portion anda second latching portion of the retainer clip are separated; andlifting the retainer clip from a retaining member.
 14. The method ofclaim 13, further comprising disengaging the first latching portion froma first engagement structure and the second latching portion from asecond engagement structure wherein the first and second engagementstructures are disposed upon the retaining member.
 15. A method ofinstalling a retainer clip comprising: squeezing a removal arm locatedon one end of a retainer clip body and a rotatable cam arm locatedgenerally in the center of the retainer clip body, wherein the cam armis rotated to a position generally parallel to the removal arm, suchthat the squeezing temporarily deforms the retainer clip body such thata first latching portion and a second latching portion of the retainerclip are separated; lowering the retainer clip onto a retaining membersuch that the first latching portion and the second latching portionadvance beyond respective first and second engagement structures locatedon the retaining member; and releasing the removal arm and the cam armsuch that the retainer clip body is no longer deformed and the first andsecond latching portions engage with their respective first and secondengagement structures.
 16. The method of claim 15, further comprisingthe act of rotating the cam arm to a position generally parallel to theretainer clip body.
 17. The method of claim 16, further comprising theact of disposing a retained component between the retainer clip body andthe retaining member.
 18. The method of claim 17, wherein the act ofrotating presses the retained component against the retaining member dueto the action of two or more cam arm side structures which extendbeneath the retainer clip body when the cam arm is generally parallel tothe retainer clip body.
 19. A heatsink retaining clip designed to securea heatsink to a heatsink retainer comprising: a body portion; a firstretaining arm coupled to the body portion; a second retaining armcoupled to the body portion; a disengagement arm coupled to the bodyportion; and a cam arm coupled to the body portion, wherein the cam armis partially rotatable from a locked position to an unlocked position.20. The heatsink retaining clip of claim 19, wherein the body portion,first retaining arm, second retaining arm, and disengagement armcomprise a single piece.
 21. The heatsink retaining clip of claim 19,wherein the first retaining arm and the second retaining arm eachfurther comprise a first hooked member and a second hooked memberrespectively such that the respective hooked members face each other.22. The heatsink retaining clip of claim 19, wherein the first retainingarm and the second retaining arm each further comprise a first windowedcutout and a second windowed cutout.
 23. The heatsink retaining clip ofclaim 19, further comprising an angled member located on the distalportion of the cam arm such that the angled member is angled away fromthe body portion when the cam arm is in the locked position.
 24. Theheatsink retaining clip of claim 19, further comprising two or more camarm side extensions such that when the cam arm is in the lockedposition, the side extensions extend downward past a lower surface ofthe body portion and when the cam arm is unlocked the side extension aresubstantially above an upper surface of the body portion.
 25. Theheatsink retaining clip of claim 19, further comprising a rotation stopdisposed along the cam arm such that the rotation stop impedes therotation of the cam arm when the rotation stop comes into contact withan upper surface of the body portion.